Content: This report presents the results of implemented the PV-Wind-Diesel hybrid mini-grid system, with a 3-phase AC-couple modular expandable component.The purpose of this work is to implement the adequate, expandability, and efﬁcient system. The Ko Jig village, a small island in the Gulf of Thailand was selected as the case study. The daily energy requirement is 265 kWh and a peak demand is 35.7 kW. The ability to pay for electricity is 0.36 Euro/kWh. The system consisted of 7.5 kWp PV, 2X5 kW wind turbines, 65 kVA diesel generator, 252 kWh battery storage, 3x2.5 kW PV inverter, 3x4.5 kW battery inverter, 4x2.5 wind turbine inverter, data acquisition system, and the 3-phase 4 wire transmission system. The system was operated since October, 2004 and wind turbines were installed in December 2006. In the beginning of the project, the participatory assessment and socio-economic impact survey were conducted. The Rural Energy Support/Service Company (RESCO) was set up with consensus of the community and cost-recovery tariff structure is developed for the project. The tariff started at 0.250 Euro/kWh and changed in responding to fuel cost by the Electricity Committee. The project used smart card prepaid kWh meters for collection of electricity tariff.

The monitoring results from October 2004 to November 2006 were evaluated and analysed. The annual average value of solar fraction was 12.93%, 11.21%, and 13.65%. The annual average value of performance ratio was 70.21%, 67.69%, and 66.26%. The yearly ﬁnal yield for 2005 is 1,123 kWh/kWp. The annual average value of capture losses was 1.33, 1.27, and 1.32 kWh/kWp.day. The annual average value of system losses was 0.39, 0.32, and 0.38 kWh/kWp.day. The speciﬁc cost of energy of PV-Diesel hybrid minigrid system results as 0.203 Euro/kWh, and the speciﬁc cost of energy of PV-Wind-Diesel hybrid mini-grid system results as 0.259 Euro/kWh.

The study shows that the PV-Wind-Diesel hybrid mini-grid system, with a three-phase AC-couple modular expandable component, has been successful to create interest among the rural people and demand from other location was received. This approach could be equally applicable to other rural village in GMS countries with similar rural conditions.